1. Field of the Invention
The present invention relates to the illuminating structure of a room lamp such that the automobile room lamp in the ON state is turned off when the sun visor is stored. More specifically, the present invention relates to the illuminating structure of a room lamp, which can be turned on/off by any operation of the user and which can be reliably turned off when the sun visor is stored.
2. Description of the Related Art
As an illumination device in the cabin of a vehicle, there are the map lamp and vanity lamp in the prior art. The map lamp is installed on the vehicle roof portion above the vehicle width-direction center of the instrument panel. On the other hand, the vanity lamp is attached on the back surface of the sun visor. Later, the map lamp and vanity lamp, which are independently attached, are replaced by a single room lamp that is shared in use. The illuminating structure of the room lamp is of the following three types.
(1) A type in which the room lamp is arranged at the stored position of the sun visor; it is automatically turned off when the sun visor is stored, and it is then automatically turned on when the sun visor is in use (see Patent Reference 1).
(2) A type in which the room lamp is arranged at the stored position of the sun visor; it is automatically turned on for use as a vanity lamp when the sun visor is in use; then it can be used as a map lamp when the sun visor is stored (see Patent Reference 2).
(3) A type wherein the room lamp is attached on the main body of the sun visor (see Patent Reference 3).
Merits and Demerits of the Invention Described in Patent Reference 1
According to the invention described in Patent Reference 1, the room lamp is arranged at the stored position of the sun visor. When the sun visor is stored at the stored position, the switch of the room lamp continues to be pressed by one end of the sun visor so that the room lamp is kept turned off. When the sun visor is in use, as the sun visor is turned out from the stored position, the switch of the room lamp that has been pressed until that time by an end of the sun visor is released, so that the room lamp is turned on to illuminate the cabin of the vehicle. According to the invention described in Patent Reference 1, the room lamp is automatically turned on/off as it is interlocked to the open/close movement of the sun visor. This is convenient. On the other hand, however, the lamp itself cannot be manually manipulated (problem A). In addition, if the sun visor shifts up, the room lamp is turned on again.
Merits and Demerits of the Invention Described in Patent Reference 2
According to the invention described in Patent Reference 2, the room lamp is arranged at the stored position of the sun visor. When the sun visor is stored at the stored position, the switch of the room lamp is pressed by an end of the sun visor so that the room lamp is turned off. When the sun visor is in use, as the sun visor is turned out from the stored position, the switch of the room lamp, which continues to be pressed up to that time by an end of the sun visor, is released so that the room lamp is turned on to illuminate the cabin of the vehicle.
In addition, according to the invention described in Patent Reference 2, a through port and a slide for opening/closing the through port are arranged on the sun visor. When the slide is moved, the through port is opened and, at the same time that the slide moves, the switch is closed so that the room lamp is automatically turned on and light passes through the through port into the cabin of the vehicle. When the slide is moved to close the through port, as the slide moves, the switch is opened, so that the room lamp is automatically turned off. According to the invention described in Patent Reference 2, the room lamp is automatically turned on/off interlocked to the opening/closing movement of the sun visor and, at the same time, the room lamp can be automatically turned off even when the slide is moved. This is convenient. However, because a through port has to be arranged on the sun visor, and a slide and a switch have to be arranged in the interior, the sun visor becomes complicated. As the structure of the sun visor becomes complicated, it is prone to problems and the cost rises (problem B).
In addition, although the circuit can be made simpler by turning on/off the lamp by a switch arranged separately instead of turning on/off of the lamp interlocked to the movement of the slide, as the lamp is hidden in the sun visor and the slide, the user may forget to turn off the hidden lamp, which is kept on (problem C).
Merits and Demerits of the Invention Described in Patent Reference 3
According to the invention described in Patent Reference 3, the room lamp is attached on the main body of the sun visor. Consequently, the operability is excellent and there is no way that the user can forget that the lamp remains on. However, in this case, it is necessary to arrange an electric circuit in the sun visor arm portion. As a result, the structure becomes complicated, and it is prone to problems. Also, the price rises (problem B).
Patent Reference 1: JP-UM-A-1-123715
Patent Reference 2: JP-A-2009-161143
Patent Reference 3: JP-A-6-127272